The NCI and NIAID of the NIH are currently investigating and treating patients with the newly described acquired immune deficiency syndrome (AIDS). About 30% of the patients with AIDS have Kaposi's Sarcoma (KS) a skin malignancy that has the capacity to spread to lymph nodes and internal organs. A significant proportion have KS limited to the skin and oropharyngeal mucous membranes. In patients without AIDS, KS has been very responsive to radiation therapy. In order to avoid the immunosuppressive effects of chemotherapy in those patients with limited disease, and in an attempt to prevent visceral spread by gaining control over skin disease, we are engaged in a trial of electron beam radiation to the entire skin. With this technique, the penetration of ionizing radiation will be limited to a depth of the patient, of less than l cm., which should not have an adverse effect on these patients already compromised immune systems.